The present invention relates to an endoscope-sheath interface using the endoscope light post. In virtually all arthroscopic procedures, the endoscope is used in combination with a sheath that attaches to the endoscope body and extends distally. The sheath serves to protect the relatively fragile endoscope and also is used to establish inflow and/or outflow channels, for irrigating fluid, surrounding the endoscope shaft. In endoscopes currently used, there exists an attachment means used to firmly secure the endoscope and sheath together axially to prevent separation during the procedure and rotationally to properly align the endoscope""s direction of view with the distal opening of the sheath. Additionally, the most popular endoscopes have a endoscope/sheath attachment that is simple and convenient so that the surgeon can install the endoscope and obturator and can disconnect the endoscope and sheath during a procedure.
Numerous variations are known in the prior art concerning attachment of the endoscope to the sheath and locking the axial and rotational alignment thereof. In all of these designs known to Applicants, multiple moving parts are provided on the sheath and/or endoscope and/or complicated manufacturing operations are required on the sheath and/or endoscope in order to provide the mechanical coupling therebetween. Couplings including those known as quick connect couplings, bayonet-style couplings, quick lock couplings, and J-lock couplings are examples of the type of couplings that are known. Applicants are aware of U.S. Pat. No. 4,254,762 to Yoon, U.S. Pat. No. 4,610,242 to Santangelo et al., 5,290,294 to Cox et al., and U.S. Pat. No. 5,456,673 to Ziegler et al. In each of these patents, an endoscope system is described including an endoscope and a sheath. None of these patents teaches or suggests employing the light post as part of the connection means between the endoscope and sheath.
Multiple moving parts on the sheath add cost, can be difficult to sterilize and clean, and suffer from long-term wear and degradation. Having to provide complicated machining on the scope increases costs and introduces intricate features that are difficult to clean. It would be advantageous and desirable to provide an attachment means that achieves axial and rotational alignment in a simple manner without requiring the use of moving parts in the sheath or complicated manufacturing operations on the endoscope. It is with this need in mind that the present
The present invention relates to an endoscope-sheath interface using the endoscope light post. The present invention includes the following interrelated objects, aspects and features:
(1) In a first aspect, the present invention contemplates a sheath sized and configured to receive in installed configuration an endoscope. For this purpose, the sheath is provided with a housing having a proximally facing opening with a U-shaped notch formed therein.
(2) The endoscope has a right-angle light post formed at its proximal end having peripheral dimensions sized and configured to be received closely within the U-shaped notch at the proximal opening of the sheath housing.
(3) A locking mechanism is provided including latch means comprising a pivotable latch having a distal end configured to be received within a notch formed on the endoscope housing distal to and diametrically opposed from the light post. The latch includes spring-biasing means tending to bias the distal portion thereof into engagement with the notch in the endoscope housing.
(4) In the preferred embodiment, a resilient O-ring is provided at the distal end of a recess in the sheath housing that is designed to slidably receive the proximal end of the endoscope. A shoulder on the distal end of the proximal portion of the endoscope compresses the O-ring when the latch is engaged. The O-ring serves to seal the proximal end of the sheath to prevent fluid leakage. Additionally, the resiliency of the O-ring provides an axial force on the endoscope to effect a secure and positive engagement of the endoscope and sheath.
Accordingly, it is a first object of the present invention to provide an endoscope-sheath interface using the endoscope light post.
It is a further object of the present invention to provide such a device wherein the light post of the endoscope is used to axially and rotatably align the endoscope within a sheath.
It is a still further object of the present invention to provide such a device wherein a latch is provided on the sheath designed to latch the endoscope in position with the light post aligned in a notch formed in a proximal opening of the sheath.
It is a still further object of the present invention to provide such a device wherein an O-ring is provided to seal and spring-load the endoscope as installed within the sheath.
These and other objects, aspects and features of the present invention will be better understood from the following detailed description of the preferred embodiment when read in conjunction with the appended drawing figures.